Mo Keshtgar, a cancer surgeon, is adapting a form of light therapy for skin cancer to be used in breast cancer, the most common cancer in Britain which kills nearly 12,000 people a year.

The treatment – known as photodynamic therapy (PDT) – uses tumour killing drugs which are injected into the body, latch onto the tumour and then are activated from outside using a laser.

The technique, which would be a huge step forward for oncology research, does not involve surgery and leaves healthy cells around the tumour unaffected.

PDT, which could become an alternative to radiotherapy in some cases, works by giving the patient a drug that makes the target area sensitive to light. The drug is activated when light – a low power red laser – is beamed at the area. The process starves the cells of oxygen, causing them to die.

Trials will be conducted at London's Royal Free Hospital, where Mr Keshtgar has been working with a technical and scientific team that includes Professor Stephen Bown of the National Medical Laser Centre, University College London and Professor Tayyeba Hasan of Harvard Medical School, Boston USA.

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Mr Keshtgar, who unveiled his technique at this year's Royal Society Summer Science Exhibition, said: "The key appeal of photodynamic therapy is that it attacks and destroys cancer cells while retaining the viability of the surrounding normal cells.

"Breast cancer can be particularly traumatic, with more invasive treatments leaving physical and emotional scars. Our treatment will keep the structure of the connective tissue intact meaning the breast does not become deformed or lose shape."

The treatment is already available for skin cancer (non-melanoma), mouth cancer, and some other cancers. But the team is the first to apply it to breast cancer. Trials are also under way with PDT for prostate and bile duct and pancreatic cancer.

Almost 45, 000 new cases of breast cancer are diagnosed in Britain every year, almost entirely all women. Fatality rates are dropping but around 11,990 women still die every year from the disease.

It is not the first time that Mr Keshtgar has pioneered a new technique. He carried out the first keyhole mastectomy in Britain.

Women treated by Mr Keshtgar had their breast removed through the side of the nipple and immediately replaced by an implant that was then inflated.

It meant some sufferers of cancer will never be without their "own" breasts and that scarring will be dramatically reduced.

Mastectomies have traditionally involved the removal of the entire breast. But some women want to keep the skin around their breasts so that implants can be inserted later and they will look more natural.